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Cover picture: Directionally selective retinal ganglion cells were studied electrophysiologically and later injected with Lucifer yellow. Responses to local movement within three zones, outlined in red, were tested. There is a subregion of the directionally selective cell's dendritic field in which the direction of movement is not discriminateda nondiscriminating zone within an otherwise directionally selective receptive field. This zone always lies on the preferred side of the receptive field (the side from which movement in the preferred direction begins). That location supports a concept of the direction-discriminating mechanism based on feed-forward inhibition; it argues against feed-forward excitation or push-pull mechanisms. For details, see the article by He et al., in this issue (pages 8049-8056). Illustration by Rebecca Rockhill.